Can you make a 7.3 IDI highway worthy

[tjh1127]

Originally Posted by RolesvilleMarina

ugh 35mph eh

yeah sell it to some hippies to park in the woods somewhere

Yea truly miserable.

[Brad_SwiftFur]

Originally Posted by Mekanic

(Ford goverend their 7.3 at 3200, Its the SAME ENGINE AS NAVSTAR!!)

No, they *ABSOLUTELY ARE NOT*!! They are very similar (virtually identical) engines but specifically the Ford version uses thicker head gaskets to allow for rod stretch at this higher RPM; there are a couple other minor differences too. Blocks, crank, pistons, heads, injectors, etc, all interchange which is why everything is widely available everywhere. I think the computers are different, since the IH uses the round plug and Ford uses the OBDII format.

[Brad_SwiftFur]

Originally Posted by Mekanic

If you want it to last do NOT turbo it. If a turbo was really needed it would have came with it.

The reason it came without a turbo is the same reason it was a 3700 model chassis in the first place, an economical basic level school bus. It was intended to trundle through residential areas picking up and dropping off kids, no need for sustained highway speeds. Turbos add cost and complexity to the engine, which kinda defeats the purpose of the base model in the first place.

Originally Posted by Booyah45828

Several companies have made turbo kits. Banks, hypermax, ATS, and a handful of small companies. Hypermax is the only one that I know of that was engineered to fit the IH chassis, the rest are designed around ford pickups and will likely require modification to make work.

The long block engine is the same. There are different engine mounts, oil coolers, manifolds, and other odds and ends between IH and Ford.

You can turbo them, which will wake them up tremendously, yet still maintain reliability. Granted, don't push 30 psi of boost through them, you'll lift the heads for sure. There are arp stud kits for them now that remedies that issue.

To this end, even the factory turbocharged some/(many?) of the IDI engines. Typical boost was probably in the 10-12 PSI range, I would hazard to say you'd be safe up to the 15 PSI range (I'll leave this to people more knowledgeable than I am.) That is, if you wanted to install a turbo on your engine in the first place.


In 1994 IH switched the 7.3 to Direct Injection and (I believe) all of 'em came turbocharged. I want to say there were different turbos for the higher HP versions and between the Ford and IH versions.